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Plasma Group History                                             Peter Smith

Studies of plasma physics began at Sussex in the early 1960's when Dr. Giuseppe Martelli set up a laboratory for experimental work. With generous help from former colleagues at Culham Laboratory, Giuseppe's first D. Phil Student, Tony Jolly, was able to design and build an apparatus that produced high-density RF-induced argon plasma for the study of wave propagation. This research was supported by Mr. John Troughton, the group's first research fellow, who was also able to provide theoretical estimates using the department's early computers. The group's first D. Phil thesis, entitled "Whistler-mode Waves in Plasma" was submitted by Tony Jolly in 1968. This original experimental machine, known as "Rig 1", was constructed 'in-house' by the group's own technician (machinist) Brian Blackman who was to provide essential support and excellent service to the group for many years until his retirement through ill-health in 1992.
Peter Smith, one of Sussex's first science graduate students, joined the plasma group in 1965 and, under Giuseppe's guidance and with help from fellow student Colin Salter, designed and constructed a hot-cathode beam-plasma machine that was to form the group's second major experimental apparatus, known as "Rig 2". Initial work on Rig 2 studied "Wave Experiments in a Magnetized Plasma" which was the subject of Peter Smith's D. Phil thesis. Both experimental rigs remained in service for many years and were used by a succession of D. Phil students for their research studies. (A listing of these later research students and their thesis topics, primarily in the areas of beam-plasma-wave interactions, is given in Appendix A.)
Giuseppe's interests soon extended to experimental studies in the earth's ionosphere. The first project used a 16" former naval gun, sited in Barbados, to study electric fields in the D, E and F regions using barium ion clouds. This technique was extended by the development of rocket-bourne payloads consisting of facing pairs of barium lined shaped charges to produce barium ion clouds in the ionosphere from locations ranging from the low latitude magnetic equator (S. India) to the high latitude auroral region (N. Norway).
Dr. Peter Christiansen joined the plasma group from Australia in 1969 as a research fellow and quickly became an indispensible member of the team through his enthusiasm for the on-going projects and the sheer breadth of his experimental and theoretical interests.
By 1979 the group's activities had extended further into ground-based studies of cratering and associated hypervelocity impact studies. This work, based at a detonics centre in southern Italy used the novel technique of a modified shaped charge to produce projectiles moving at ~1km/sec which were photographed at very high speed to record the cratering processes. Related work was also carried out at Sussex by measurement of light and electomagnetic emmissions from rock specimens during fracture.
In 1985, Giuseppe's partner, Ms. Pamela Rothwell, moved fom the University of Southampton to Sussex to extend the group's activities even further to include optical observations of atmosperic dust, aerosol content and auroral instabilities. The auroral studies were complemented by involvement in the European Incoherent Scatter Radar (EISCAT) and the group enjoyed a very active programme of joint sounding rocket - EISCAT experiments based in the auroral regions of arctic Norway. During this period, the group were leaders in the development of cooled integrating CCD cameras used to image and digitally record auroral activity.
Dr. Paul Gough joined the group also from Southampton in 1990 and, with help from Dr. Andrew Buckley, subsequently completed the group's transition from plasma physics to plasma and space physics by setting up the Space Centre Centre in the School of Engineering following the sad passing through ill-health of the group's key members (Pamela Rothwell-Martelli in 1991, Peter Christiansen in 1992 and Giuseppe Martelli in 1994).
Dr Richard Rijnbeek became the head of the Space and Plasma Physics Group in 1995 and continued space-plasma activities with valuable contributions from Russian colleagues until the group was unfortunately forced to close due to lack of funding in 2002. The activities of the Space Science Centre are described more fully in the accompanying text.

Appendix A

Whistler-Mode Waves in Plasma (D. Phil.) by A. B. Jolly, May 1968.

Charged Particle Motion in a Time-Dependent Electromagnetic Field (M. Sc.) by M. L. Woolley, July 1968.

Measurements of Ion Temperatures and Drift Velocities in an Argon Plasma using a Retarding Field Ion Energy Analyzer (M. Sc.) by A. Medhi, July 1969.

Measurements using Barium Ion Clouds in the Ionospheric D, E and F Regions (D. Phil.) by J. R. W. Hunter, June 1970.

The Interaction between a Charged Particle and Electromagnetic Wave in a Uniform Magnetic Field (D. Phil.) by M. L. Woolley, July 1970.

Fast Electron Beam - Helicon Wave Interactions in a Laboratory Plasma (M. Sc.) by C. Christopoulos, July 1970.

The Theory and Interpretation of Artificial Ion Clouds (D. Phil.) by M. J. Giles, October 1970.

Photocathode Sensitivity Enhancement by Total Internal Reflection (M. Sc.) by S. A. Hamadto, August 1971.

Development of the Shaped Charge Technique for Ionospheric Research (D. Phil.) by H. M. Hilmi, January 1972.

Beam-Plasma Experiments (D. Phil) C. A. Nyak, August 1973.

Wave Experiments in a Magnetized Plasma (D. Phil) by P. N. Smith, April 1974.

Experiments with Whistler Waves (D. Phil.) by C. Christopoulos, June 1974.

The Production of a Whistler Mode Wave through the Nonlinear Coupling of Two High-Frequency Electromagnatic Waves in a Plasma (D. Phil.) by N. D. Wells, September 1977.

Photometric Observations of Auroral Oscillations (D. Phil.) by S. Singh, December 1980.

Hypervelocity Impact Studies (D. Phil.) by P. J. Hurren, October 1983.

Microcratering of Polished Surfaces (D. Phil.) by E. Etemadi, October 1984.

Laboratory Simulation of Asteroid and Meteor Impact (D. Phil.) by A. J. Woodward, April 1987.

Computer Simulation of Electron Plasma Waves (M. Sc.) by A. E. Mohamad, July 1991.

An Automatic Auroral Imaging System (D. Phil.) by S. A. Coles, September 1992.

Radar Studies of Auroral Phenomena (D. Phil.) by N. G. J. Gazey, April 1994.

Development and Use of Software for the Analysis of Hypervelocity Impact Experiments (D. Phil.) by I. Giblin, September 1994.

Simulations of Electron Whistler-Mode Waves in an Anisotropic Plasma (D. Phil.) by P. Devine, March 1995.